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Abstract  

An ice-core of 4 m length was drilled at the Jungfraujoch. It was divided into 18 sections and analyzed for solid and dissolved material by neutron activation analysis using nondestructive counting as well as chemical group separations. The solid material was identified as stone dust. Part of the dissolved material seems to originate from dissolved limestone, whereas many elements can not be accounted for by this hypothesis and must be due to atmospheric fallout.

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Abstract  

Radon exhalation rate from various types of stones, used inside the living buildings, is a major factor for evaluation of the environmental radon level. To verify the significance and lethal impacts of this unknown and obscure source of radiation upon the people around the world, the exhaled radon gas concentrations from the rocks, granodiorite, granite, limestone and aragonite, and the effect of their block sizes on the exhalation rate, have been studied. The block samples, collected from their ores, were transferred to plastic containers in which the CR-39 detectors could properly be placed and air tightened, for concentration measurements. The results show the radon concentration of 7.4 ± 0.8, 6.6 ± 0.6, 0.08 ± 0.02 and 0.09 ± 0.02 kBq m−3 for granodiorite, granite, limestone and aragonite, respectively. The corresponding annual dose values in a closed environment are: 186 ± 20, 166 ± 15, 2.5 ± 1 and 2 ± 1 mSv y−1. These absorbed dose values indicate that granodiorite and granite when used inside the buildings could increase the risk of various cancers while aragonite and limestone have much lower risks and are recommended for use inside the buildings. The former ones when used in the closure areas remedial action should be implemented. The results do not show obvious dependence between the rock size of the samples and their radon exhalation rate.

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In the area where the Darnó Fault belt breaks up as a horsetail fault system in southern Slovakia and northwestern Hungary, beside the dominant lithologies such as calcareous siltstone and claystone several peculiar lithofacies generated in different paleoenvironments of the Buda (Hungarian) Paleogene and Fiľakovo/Pétervásara Eggenburgian Basins occur. Laminated limestone and shale classified as oil shale from the village of Drienovec, the Szendrö and the Bátka vicinities (Eocene-Oligocene and Early Miocene in age) came to existence in coastal lagoons and/or subtidal lagoons under anaerobic conditions at the bottom and affected by seasonal weather changes. The Bátka, Novaj, Budikovany, Bretka bioclastic and organogenic limestone units (Kiscellian and Egerian in age respectively) were deposited under shallow marine littoral conditions. The Drienovec and Szuhogy Conglomerate units originated under fluviatile conditions. Almost all mentioned lithologies were generated in genetic (conglomerate) or spatial (oil shale) relationship to the Darnó Fault Belt. The Bátka Limestone as well as the Hostišovce Member are related to the Šafárikovo Rise, a faulted structure perpendicular to the course of the Darnó Fault Belt.

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Bedrock has an essential role in the formation of soils, it fundamentally determines mineral composition. The present research focuses on the minerals in forest soils formed in the Bükk Mountains (NE Hungary). The composition of soil minerals was in accordance with the geological features as well as with the changes in climate and vegetation, which provide a basis for tracking the past of the soil formation mechanisms (Nemecz, 2006). Thus, by studying the mineral composition the formation processes and development of the soils can be unveiled.According to the findings it can be assumed that the investigated soils, although formed primarily on solid limestone, cannot be the products of the weathering of limestone solely, as they also contain significant amounts of silicates. The major part of the soil forming materials presumably originates from earlier dust fallings or from alluvial deposits by erosion. The former assumption is confirmed by the fact that the investigated area is located at a high altitude, thus significant amounts of eroded material could only originate from a short distance, where the bedrock also consists of limestone. Further research is needed for more detailed knowledge on the mineral composition of the soils, thus on the development of the soils and the bedrock of the investigated area.

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Abstract  

Simultaneous thermogravimetry (TG) and differential thermal analysis (DTA) were applied to light crude oil combustion in the presence and absence of metal oxide. In crude oil-limestone mixture, three main transitional stages are detected. These are distillation, low-temperature oxidation (HTO) and high temperature oxidation (HTO) regions respectively. In the case of experiments with Fe(III)-chloride at different amounts, the shape of TG-DTA curve is changed considerably. Kinetic parameters of the samples are determined using ASTM method. Reduction in activation energy is considered to be an indication of the catalytic activity of the additive.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: M. Kocsis, L. Nyikos, I. Szentpétery, D. Horváth, J. Kecskeméti, A. Lovas, T. Pajkossy, and L. Pócs

Abstract  

An attempt was made to detect neutrons from the so-called cold nuclear fusion of deuterium in palladium and titanium, both saturated with deuterium: the palladium electrolytically and the titanium from gas phase. The measurements were performed in a tunnel located 30 m deep in limestone, using3He filled proportional counters surrounded by water for neutron moderation. In all cases the detected neutron flux was practically equal to the background level. Very low upper limits to the neutron source strength were obtained from this experiment: 2×10–4 n.s–1g–1 Pd and 4.3×10–4 n.s–1g–1 Ti on the 1 level.

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Abstract  

Samples of sediments taken from the River Saale at different locations were investigated by thermogravimetry, differential thermal analysis, mass spectrometry and FTIR spectroscopy.The thermal behaviour of these sediments varied significantly depending on contents of organic and inorganic compounds. The variable organic loading resulted from the different degrees of treatment of communal or industrial waste water. Mass spectrometric investigations in the lower temperature ranges demonstrated humic substances as essential components.The mineral components in the river sections of the slate mountains differed significantly from those of the shell limestone. The results of FTIR analysis of these samples confirmed well with the findings of thermoanalytical investigations.

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Abstract  

As a part of a project aimed at precise correlation of the Jurassic–Cretaceous (J/K) boundary interval in the Tethyan and Boreal realms, neutron and photon activation analyses were employed in geochemical characterization of limestone samples from the Brodno section, Slovakia, which offers a record of hemipelagic marine sediments around the J/K boundary in the Tethyan realm. Nickel and antimony anomalies exceeding almost twenty times the levels in neighboring beds were found near the beds assigned recently to the J/K boundary. Elucidation of their origin (volcanism, isochronous meteoritic impact, concentrating in, e.g., sulfides) requires further investigation.

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Twenty Roman Age home-made sherds from Central Italian San Potito locality were studied by petrographic microscopic method. The ceramics were divided into five petrographic groups on the basis of their composition and structural-textural features. Two groups of the ceramics were tempered with clasts of alkaline volcanic origin, which seem to originate from Central-Italian volcanic territory components. The ceramics belonging to the other three groups contained large amounts of limestone and carbonatic fossils, the origin of the raw material was a marine clayish sediment, perhaps flysch.

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Abstract  

Neutron activation analysis (NAA) is a very sensitive and accurate multielement analytical method that is widely applied to the investigation of environmental and archaeological problems. The first part of this paper is a review of pollution studies of toxic trace elements in sediments, seawater and marine organisms of Saronikos Gulf, Greece by NAA. The second part of this paper is a review of provenance studies based on minor and trace element research in ancient ceramics, obsidian, flint, limestone, marble and lead by Instrumental NAA, performed at the NCSR Demokritos.

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